The page http://www.videolan.org/ behaves oddly with 64-bit IE.
When using 64-bit version of Internet Explorer the page offers vlc download for "Mac OS X 10.5". When I use 32-bit version of IE or Firefox the page offers Windows version of the file. It doesn't matter if the computer has 64-bit Vista or Windows 7. The 64-bit version of IE causes similar behavior on both.
Luckily there is link "Other systems, version" that you can use to overcome the selection.